Streaming is a technique for breaking up a media file into packets and sending those packets to the user in sequence, via a packet network such as the Internet or intranet. A receiving computer is able to play the data when it arrives, instead of waiting for the entire file to download. Audio streaming is an extremely popular application on the Internet today, as evidenced by the immense popularity of music and other audio content in the MP3, RealAudio, and Microsoft Media formats. With the increasing proliferation of cellular users, and the trend towards ubiquitous services, it is believed that there could also be an enormous demand for similar streaming applications to cellular phone users, should such capability be developed. A recent study by Arbitron found that over 75% of polled web users expressed interest in portable streaming services, saying they would increase their tuning into streaming programs if these services were available on portable devices.
Audio streaming over the Internet uses a packet-based approach, where the audio source is broken down into packets, each packet is encoded, and sent to the receiving client in sequence. The client receives the packets, decodes them, and plays them out on the receiving terminal. Unfortunately, cellular systems today cannot offer such Internet-style packet-based audio streaming due to limitations at the terminal (client cell phone) and due to limitations of the infrastructure. For example, cellular phones can not support streaming since they do not have decoders (e.g. mp3 decoder) or streaming controls (skip, pause, etc.). Additionally, data rates over the cellular networks today are quite limited and are insufficient to transport encoded streaming packets.